Regulations with regards to chemical substances have been more rigorous along with growing worldwide environmental problems. For example, the use of six special harmful substances is prohibited by EU:RoHS (European Restriction of Hazardous Substances in Electrical and Electronic Equipment). Further, chemical substances including Substances of Very High Concern (SVHC) are controlled by REACH (Registration, Evaluation, Authorisation and Restrictions of Chemicals) which is a regulation regarding the registration, evaluation, authorisation and restrictions of chemical substances. As mentioned above, in recent years, regulations with regards to chemical substances have been more rigorous.
In the meantime, antimony is added as a clarifying agent to glass which we use frequently. Antimony is an element which is a homologue of arsenic and can be probably a substance of SVHC regulated by REACH. Because antimony is different in toxicity depending on valency, it is desired to develop a method enabling the analysis of antimony according to its valency.
For analyzing antimony (III) and antimony (V) according to its valency, an analytical method which is a combination of the solvent extraction and hydride separation ICP method has been tried so far (for example, JP-A 2000-317205 (Kokai)).
However, the above method has the drawback that in the case of intending to analyze antimony contained in glass according to its valency, it is necessary to dissolve the glass once by using a hydrofluoric acid solution and then to measure antimony contained in the hydrofluoric acid solution, and this operation cannot be carried out in the above method.